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Top 3 Longest Calls Per Account
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Top 3 Longest Calls Per Account

MediumSQL · PostgreSQL

Problem

Aircall wants to review the longest calls handled for each customer account during a reporting month. Write a SQL query to return each account's three longest calls during September 2026.

Output

  1. One row per qualifying call, with columns account_id, account_name, call_id, started_at, duration_seconds, and call_rank
  2. Include only calls associated with a customer account and started during September 2026
  3. Rank calls independently within each account by duration descending; calls with a NULL duration are placed after calls with measured durations, and call_id breaks duration ties
  4. Return only ranks 1 through 3. Accounts with fewer than three qualifying calls may have fewer rows
  5. Order by account_id, then call_rank

Schema

customer_accounts
ColumnTypeDescription
account_idPKINTUnique Aircall customer account identifier
account_nameVARCHAR(120)Customer account display name
calls
ColumnTypeDescription
call_idPKINTUnique call identifier
account_idINTCustomer account associated with the call
started_atTIMESTAMPTZCall start timestamp
duration_secondsINTCall duration in seconds
Tablescustomer_accountscalls
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